| Spicestag Ltd | Manufacturing | 2025 |
| Spiral Investment Limited | Real estate | 2020 |
| Spire Services Limited | Transport & logistics | 2018 |
| Splash and More Entertainment Limited | Arts & recreation | 2026 |
| Spnr Investments Ltd | Construction | 2018 |
| Sporty Textile Limited | Wholesale & retail | 2022 |
| Spread Away Ltd | Administrative & support | 2016 |
| SQD UK Trading Ltd | Transport & logistics | 2025 |
| Squad Merlin Ltd | Construction | 2015 |
| SRA Capital CA (AIL) Ltd | Administrative & support | 2023 |
| Srag Ltd | Real estate | 2025 |
| SS Construction Enterprise Ltd | Construction | 2024 |
| SS Install Group Ltd | Construction | 2026 |
| SS U.K. Property Investment Ltd | Real estate | 2024 |
| SS. Design & Fit Limited | Construction | 2025 |
| SS218 Limited | Health & social care | 2015 |
| SSM (London) Investments Ltd | Administrative & support | 2025 |
| SSM Trading Ltd | Real estate | 2019 |
| SSS Car Rentals Ltd | Administrative & support | 2023 |
| SSS Cool Air Ltd | Construction | 2024 |
| ST Clean Ltd | Administrative & support | 2024 |
| ST George Consultancy Services Ltd | Health & social care | 2026 |
| ST George Security Services Ltd | Public administration | 2018 |
| ST Helier OFF Licence Ltd | Wholesale & retail | 2024 |
| ST Spraying Ltd | Construction | 2023 |
| STA Diagnostics Ltd | Wholesale & retail | 2026 |
| Stackwell Studios Limited | Information & communication | 2025 |
| Stagglife Ltd | Professional & scientific | 2025 |
| Stam 78 Construction Ltd | Construction | 2015 |
| Stannick Data Ltd | Information & communication | 2020 |
| Star & Star Ltd | Real estate | 2022 |
| Star & Stark Ltd | Transport & logistics | 2023 |
| Star Travel & Tours Limited | Administrative & support | 2022 |
| Star-D Ltd | Other services | 2022 |
| Starlight Property Developers Ltd | Real estate | 2021 |
| Starline Global Freight Services Ltd | Transport & logistics | 2025 |
| Stars Removal Ltd | Transport & logistics | 2015 |
| Start UP Business Advisors Ltd | Professional & scientific | 2017 |
| Startbusinessonline Ltd | Administrative & support | 2024 |
| Startnet Limited | Administrative & support | 1998 |
| Station Road Property Limited | Hospitality | 2014 |
| Stcc Private Limited | Construction | 2025 |
| Steed Energy Solutions Limited | Wholesale & retail | 2024 |
| Steel Guard Ltd | Construction | 2025 |
| Stella Healthcare Limited | Health & social care | 2015 |
| Step UP Teaching Limited | Education | 2023 |
| Stepfast Logistics Ltd | Transport & logistics | 2025 |
| Stepstone Properties UK Ltd | Households | 2017 |
| Sterling Estate Solutions Limited | Real estate | 2025 |
| Sterling Metal Trading Limited | Wholesale & retail | 2025 |
| Sterling Stitch Limited | Wholesale & retail | 2025 |
| Stich London Ltd | Construction | 2019 |
| Stickyworld Limited | Information & communication | 2010 |
| STM Fashion Ltd | Wholesale & retail | 2013 |
| STN Drylining Limited | Construction | 2021 |
| Stockwell Convenience Stores Ltd | Wholesale & retail | 2019 |
| Stockwell Fast Food Limited | Hospitality | 2019 |
| Stonecot Fades Ltd | Other services | 2022 |
| Stonefield Innovations Ltd | Information & communication | 2022 |
| Stonemountain Ventures Ltd | Information & communication | 2020 |
| Stories Coffee Limited | Hospitality | 2021 |
| STR Groundworks Ltd | Construction | 2019 |
| Stratford Southern Limited | Extraterritorial | 2014 |
| Stratix Solutions Ltd | Professional & scientific | 2025 |
| Stratton Advisory Ltd | Information & communication | 2026 |
| Stride Deliveries Ltd | Wholesale & retail | 2020 |
| Structura London Ltd | Professional & scientific | 2025 |
| Studio Doohan Ltd | Professional & scientific | 2025 |
| Studio Shuhaiber Limited | Wholesale & retail | 2025 |
| Studio VNA Ltd | Professional & scientific | 2025 |
| Style by Seven Ltd | Wholesale & retail | 2021 |
| Styles Studio Limited | Administrative & support | 2019 |
| SU Building Services Limited | Professional & scientific | 2016 |
| Suave Property Surveyors Ltd | Professional & scientific | 2022 |
| SUB Continental Foods Limited | Wholesale & retail | 2020 |
| Subhan Holdings Limited | Real estate | 2019 |
| Subhan Services Ltd | Other services | 2016 |
| Subs London Trading Ltd | Wholesale & retail | 2021 |
| Substar Limited | Wholesale & retail | 2011 |
| Success Buddies Ltd | Wholesale & retail | 2015 |
| Success From Within Ltd | Other services | 2023 |
| SUD Property Ltd | Real estate | 2022 |
| Sudacell Limited | Wholesale & retail | 2024 |
| Sudheha Studios Ltd | Professional & scientific | 2026 |
| Sufi Investments Limited | Real estate | 2017 |
| Sugarbush Landscapes Ltd | Administrative & support | 2022 |
| SUJ Properties Ltd | Real estate | 2024 |
| Sukh Food Services Ltd | Hospitality | 2026 |
| Sulisluna UK Limited | Wholesale & retail | 2020 |
| Sultan Technical Ltd | Construction | 2026 |
| Sultan Trends Ltd | Hospitality | 2025 |
| Summerhill Health Limited | Health & social care | 2021 |
| Summit Financial Services (London) Limited | Professional & scientific | 2025 |
| Sun Distributors UK Limited | Wholesale & retail | 2011 |
| Sunami Motorcycles Ltd | Wholesale & retail | 2017 |
| Sunrich Foods Ltd | Wholesale & retail | 2013 |
| Sunsam Holdings Ltd | Financial services | 2026 |
| Sunsam Limited | Health & social care | 2014 |
| Sunsam Property Investment Ltd | Real estate | 2026 |
| Sunstar Group Limited | Real estate | 1990 |